/* atxp1.c - kernel module for setting CPU VID and general purpose I/Os using the Attansic ATXP1 chip. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include <linux/kernel.h> #include <linux/init.h> #include <linux/module.h> #include <linux/jiffies.h> #include <linux/i2c.h> #include <linux/hwmon.h> #include <linux/hwmon-vid.h> #include <linux/err.h> #include <linux/mutex.h> #include <linux/sysfs.h> #include <linux/slab.h> MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("System voltages control via Attansic ATXP1"); MODULE_VERSION("0.6.3"); MODULE_AUTHOR("Sebastian Witt <se.witt@gmx.net>"); #define ATXP1_VID 0x00 #define ATXP1_CVID 0x01 #define ATXP1_GPIO1 0x06 #define ATXP1_GPIO2 0x0a #define ATXP1_VIDENA 0x20 #define ATXP1_VIDMASK 0x1f #define ATXP1_GPIO1MASK 0x0f static const unsigned short normal_i2c[] = { 0x37, 0x4e, I2C_CLIENT_END }; static int atxp1_probe(struct i2c_client *client, const struct i2c_device_id *id); static int atxp1_remove(struct i2c_client *client); static struct atxp1_data * atxp1_update_device(struct device *dev); static int atxp1_detect(struct i2c_client *client, struct i2c_board_info *info); static const struct i2c_device_id atxp1_id[] = { { "atxp1", 0 }, { } }; MODULE_DEVICE_TABLE(i2c, atxp1_id); static struct i2c_driver atxp1_driver = { .class = I2C_CLASS_HWMON, .driver = { .name = "atxp1", }, .probe = atxp1_probe, .remove = atxp1_remove, .id_table = atxp1_id, .detect = atxp1_detect, .address_list = normal_i2c, }; struct atxp1_data { struct device *hwmon_dev; struct mutex update_lock; unsigned long last_updated; u8 valid; struct { u8 vid; /* VID output register */ u8 cpu_vid; /* VID input from CPU */ u8 gpio1; /* General purpose I/O register 1 */ u8 gpio2; /* General purpose I/O register 2 */ } reg; u8 vrm; /* Detected CPU VRM */ }; static struct atxp1_data * atxp1_update_device(struct device *dev) { struct i2c_client *client; struct atxp1_data *data; client = to_i2c_client(dev); data = i2c_get_clientdata(client); mutex_lock(&data->update_lock); if (time_after(jiffies, data->last_updated + HZ) || !data->valid) { /* Update local register data */ data->reg.vid = i2c_smbus_read_byte_data(client, ATXP1_VID); data->reg.cpu_vid = i2c_smbus_read_byte_data(client, ATXP1_CVID); data->reg.gpio1 = i2c_smbus_read_byte_data(client, ATXP1_GPIO1); data->reg.gpio2 = i2c_smbus_read_byte_data(client, ATXP1_GPIO2); data->valid = 1; } mutex_unlock(&data->update_lock); return data; } /* sys file functions for cpu0_vid */ static ssize_t atxp1_showvcore(struct device *dev, struct device_attribute *attr, char *buf) { int size; struct atxp1_data *data; data = atxp1_update_device(dev); size = sprintf(buf, "%d\n", vid_from_reg(data->reg.vid & ATXP1_VIDMASK, data->vrm)); return size; } static ssize_t atxp1_storevcore(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct atxp1_data *data; struct i2c_client *client; int vid, cvid; unsigned int vcore; client = to_i2c_client(dev); data = atxp1_update_device(dev); vcore = simple_strtoul(buf, NULL, 10); vcore /= 25; vcore *= 25; /* Calculate VID */ vid = vid_to_reg(vcore, data->vrm); if (vid < 0) { dev_err(dev, "VID calculation failed.\n"); return -1; } /* If output enabled, use control register value. Otherwise original CPU VID */ if (data->reg.vid & ATXP1_VIDENA) cvid = data->reg.vid & ATXP1_VIDMASK; else cvid = data->reg.cpu_vid; /* Nothing changed, aborting */ if (vid == cvid) return count; dev_dbg(dev, "Setting VCore to %d mV (0x%02x)\n", vcore, vid); /* Write every 25 mV step to increase stability */ if (cvid > vid) { for (; cvid >= vid; cvid--) { i2c_smbus_write_byte_data(client, ATXP1_VID, cvid | ATXP1_VIDENA); } } else { for (; cvid <= vid; cvid++) { i2c_smbus_write_byte_data(client, ATXP1_VID, cvid | ATXP1_VIDENA); } } data->valid = 0; return count; } /* CPU core reference voltage unit: millivolt */ static DEVICE_ATTR(cpu0_vid, S_IRUGO | S_IWUSR, atxp1_showvcore, atxp1_storevcore); /* sys file functions for GPIO1 */ static ssize_t atxp1_showgpio1(struct device *dev, struct device_attribute *attr, char *buf) { int size; struct atxp1_data *data; data = atxp1_update_device(dev); size = sprintf(buf, "0x%02x\n", data->reg.gpio1 & ATXP1_GPIO1MASK); return size; } static ssize_t atxp1_storegpio1(struct device *dev, struct device_attribute *attr, const char*buf, size_t count) { struct atxp1_data *data; struct i2c_client *client; unsigned int value; client = to_i2c_client(dev); data = atxp1_update_device(dev); value = simple_strtoul(buf, NULL, 16); value &= ATXP1_GPIO1MASK; if (value != (data->reg.gpio1 & ATXP1_GPIO1MASK)) { dev_info(dev, "Writing 0x%x to GPIO1.\n", value); i2c_smbus_write_byte_data(client, ATXP1_GPIO1, value); data->valid = 0; } return count; } /* GPIO1 data register unit: Four bit as hex (e.g. 0x0f) */ static DEVICE_ATTR(gpio1, S_IRUGO | S_IWUSR, atxp1_showgpio1, atxp1_storegpio1); /* sys file functions for GPIO2 */ static ssize_t atxp1_showgpio2(struct device *dev, struct device_attribute *attr, char *buf) { int size; struct atxp1_data *data; data = atxp1_update_device(dev); size = sprintf(buf, "0x%02x\n", data->reg.gpio2); return size; } static ssize_t atxp1_storegpio2(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct atxp1_data *data; struct i2c_client *client; unsigned int value; client = to_i2c_client(dev); data = atxp1_update_device(dev); value = simple_strtoul(buf, NULL, 16) & 0xff; if (value != data->reg.gpio2) { dev_info(dev, "Writing 0x%x to GPIO1.\n", value); i2c_smbus_write_byte_data(client, ATXP1_GPIO2, value); data->valid = 0; } return count; } /* GPIO2 data register unit: Eight bit as hex (e.g. 0xff) */ static DEVICE_ATTR(gpio2, S_IRUGO | S_IWUSR, atxp1_showgpio2, atxp1_storegpio2); static struct attribute *atxp1_attributes[] = { &dev_attr_gpio1.attr, &dev_attr_gpio2.attr, &dev_attr_cpu0_vid.attr, NULL }; static const struct attribute_group atxp1_group = { .attrs = atxp1_attributes, }; /* Return 0 if detection is successful, -ENODEV otherwise */ static int atxp1_detect(struct i2c_client *new_client, struct i2c_board_info *info) { struct i2c_adapter *adapter = new_client->adapter; u8 temp; if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) return -ENODEV; /* Detect ATXP1, checking if vendor ID registers are all zero */ if (!((i2c_smbus_read_byte_data(new_client, 0x3e) == 0) && (i2c_smbus_read_byte_data(new_client, 0x3f) == 0) && (i2c_smbus_read_byte_data(new_client, 0xfe) == 0) && (i2c_smbus_read_byte_data(new_client, 0xff) == 0))) return -ENODEV; /* No vendor ID, now checking if registers 0x10,0x11 (non-existent) * showing the same as register 0x00 */ temp = i2c_smbus_read_byte_data(new_client, 0x00); if (!((i2c_smbus_read_byte_data(new_client, 0x10) == temp) && (i2c_smbus_read_byte_data(new_client, 0x11) == temp))) return -ENODEV; /* Get VRM */ temp = vid_which_vrm(); if ((temp != 90) && (temp != 91)) { dev_err(&adapter->dev, "atxp1: Not supporting VRM %d.%d\n", temp / 10, temp % 10); return -ENODEV; } strlcpy(info->type, "atxp1", I2C_NAME_SIZE); return 0; } static int atxp1_probe(struct i2c_client *new_client, const struct i2c_device_id *id) { struct atxp1_data *data; int err; data = kzalloc(sizeof(struct atxp1_data), GFP_KERNEL); if (!data) { err = -ENOMEM; goto exit; } /* Get VRM */ data->vrm = vid_which_vrm(); i2c_set_clientdata(new_client, data); data->valid = 0; mutex_init(&data->update_lock); /* Register sysfs hooks */ if ((err = sysfs_create_group(&new_client->dev.kobj, &atxp1_group))) goto exit_free; data->hwmon_dev = hwmon_device_register(&new_client->dev); if (IS_ERR(data->hwmon_dev)) { err = PTR_ERR(data->hwmon_dev); goto exit_remove_files; } dev_info(&new_client->dev, "Using VRM: %d.%d\n", data->vrm / 10, data->vrm % 10); return 0; exit_remove_files: sysfs_remove_group(&new_client->dev.kobj, &atxp1_group); exit_free: kfree(data); exit: return err; }; static int atxp1_remove(struct i2c_client *client) { struct atxp1_data * data = i2c_get_clientdata(client); hwmon_device_unregister(data->hwmon_dev); sysfs_remove_group(&client->dev.kobj, &atxp1_group); kfree(data); return 0; }; static int __init atxp1_init(void) { return i2c_add_driver(&atxp1_driver); }; static void __exit atxp1_exit(void) { i2c_del_driver(&atxp1_driver); }; module_init(atxp1_init); module_exit(atxp1_exit);